COMMISSION 27 OF THE I. A. U.
          INFORMATION BULLETIN ON VARIABLE STARS
                      Number 1814

                                    Konkoly Observatory
                                    Budapest
                                    1980 July 10




          THE LIGHT CURVE OF STEPANIAN'S STAR



    Photoelectric observations of Stepanian's star were made
on April 19-22 of this year. The two-beam, multi-mode, nebular-
stellar photometer of the National Observatory of Athens was used
attached to the 48-inch Cassegrain reflector at Kryonerion Station. 
Dry ice was used to freeze the photomultiplier. The filters
used, B and V, are in close accordance with the standard ones.
    Horne et al. (1980a) discovered that this star is an eclipsing 
binary. Using Horne et al. (1980a) and Horne et al. (1980b)
ephemeris formulae the following values for the residuals (O-C)_a
and (O-C)_b were found, respectively, for the observed primary
minimum:
    Hel. J.D.        (O-C)_a         (O-C)_b
    2444349.5908    -0.0028          -0.0070


                  [FIGURE 1]

              RA    = 15h 35m 44s
              Decl. =+19d 01' 30"

Fig.1. The field of Stepanian's star. (After Stepanian, 1979).
     The underlined star is that one which served as comparison.

    Figure 1 gives the variable's field (after Stepanian, 1979)
where the star which served as comparison (the underlined) and
the variable itself are denoted. Since the two stars are very

close to each other, no extinction reduction has been made. Moreover, 
no colour reduction has been made since the colour indices
for both stars are not known.


                   [FIGURE 2]

Fig.2. The light curve of Stepanian's star in B and V.

  In Figure 2 the obtained light curve is represented in B
and V. One can notice a lot of irregularities outside eclipses.
Unfortunately there are no observations around secondary minimum.
The observations will be continued during August and September.



  P. ROVITHIS
National Observatory of
Athens, Athens (306), Greece



References:
Horne, K., Cohen, J., Oke, J.B. and Mochnacki, S.W.:.1980a, I.A.U.
        Circ. No. 3462 [BIBCODE 1980IAUC.3462....3H ]
Horne, K., Margon, B. and Africano, J.: 1980b, I.A.U. Circ.No.3466 [BIBCODE 1980IAUC.3466....3H ]
Stepanian, J.A.: 1979, I.B.V.S. No. 1630